But not the Hippopotamus/Armadillo

Morgan has this cute baby board book by Sandra Boynton called "But not the Hippopotamus." It's about a bunch of silly little animals that hang out together, but the hippo is alone. It describes all these activities the animals do together...intermixed with "but not the hippopotamus" and then shows a picture of the hippo wistfully watching the other animals interact. Towards the end of the book the animals invite the hippo to come join them which of course she excitedly accepts. Then the last page ends with "but not the armadillo" and shows a sad picture of an armadillo all alone. Morgan always ends this book by saying "a-day-o" which of course is "armadillo". I think it's funny that even with the numerous time she hears "hippopotamus" at the end she just repeats the last word "armadillo". A few times when she brings me the book to read (by the way, "book" is "b-b-b-b"), she will say "a-day-o" right away. Its definitely the "armadillo" book, not the "hippopotamus" book.